Femoral Cartilage Thickness and Vitamin D Level in Systemic Sclerosis Patients and Relation to Disease Severity

Abstract

Background: Systemic sclerosis (SSc) is a heterogeneous autoimmune disorder associated with vascular dysfunction and fibrotic changes. Low vitamin D levels and decreased femoral cartilage thickness (FCT) have been observed in SSc. Objectives: This study aimed to evaluate the relation between serum level of vitamin D and FCT among SSc patients and to correlate both with clinical features and disease severity score. Patients and Methods: This study included 40 SSc patients, divided into 2 groups; group 1: sufficient vitamin D (level > 30 ng/ml), group 2: insufficient vitamin D (level < 30 ng/ml). All patients were subjected to history taking, clinical examination, and assessment of disease severity by Medsger Disease Severity Index (MDSI), laboratory investigations, 25 (OH) vitamin D level and musculoskeletal ultrasound of both knees to assess FCT. Three midpoint measurements of FCT were taken from each knee: lateral femoral condyle (LFC), femoral intercondylar area (ICA) and medial femoral condyle (MFC). Results: Thin FCT was found in 60% of patients. There was insufficient vitamin D level in 65% of patients. Age was negatively correlated with FCT at right MFC area and female parity was also negatively correlated with right ICA and MFC areas. FCT was significantly lower in group 1 at areas of left MFC and LFC areas, but no relation between femoral cartilage thickness and vitamin D level with disease severity. Conclusion: There is significant relation between femoral cartilage thickness and vitamin D level in scleroderma patients, both decline in SSc patients but not related to disease severity score.